The following correction was printed in the Guardian's Corrections and clarifications column, Tuesday January 15 2008 ICI did not merge with Zeneca, as was stated in the obituary below. Zeneca was formed after ICI's pharmaceuticals and agrochemicals businesses were demerged from the main company in June 1993.

Sir John Harvey-Jones, who has died aged 83, was a genial and genuine giant of British industry - the sort of man with whom a bear hug and a belly laugh seemed the most appropriate greeting once you got to know him ... which took about five minutes. He was best known as the star of the BBC Troubleshooter programmes, which ran to five series and several specials in the 1990s, in which he roamed the nation's assembly lines, telling other people how to run their businesses.

But what made him so remarkable was that he emerged in the early 1980s, when virtually every other British industrialist looked a puny, third-rate failure in a grey suit. His generation may have produced people such as Lord Hanson and Sir James Goldsmith, who left the country to pillage, financially, abroad, and buccaneers such as Sir Freddie Laker and Sir Richard Branson, but Harvey-Jones was a swashbuckler who was, miraculously, made chairman of that most pukka of British companies, ICI (Imperial Chemical Industries). And this at a time when the rest of the country's heavy industries - British Leyland, Triumph and Norton motorcycles, the mines, shipyards and steel industry - were disappearing down the commercial plughole.

It is hard now to remember what a bizarre choice he was back in 1982. Margaret Thatcher and her acolytes Norman Tebbit and Keith Joseph were espousing the radical faith of complete laissez-faire economics, and City whizz kids were piling up a paper fortune on the stock market.

In the real world of unemployment and the collapsing industrial economy, ICI had just clocked up its first ever quarterly loss. Everyone expected the company, a bellwether of British manufacturing, to appoint another grey suit just to keep the corporation alive.

Instead it got Harvey-Jones, with his shock of dark hair, trademark moustache, baggy brown suits and wild ties. Who could have guessed that Britain's foremost chemicals company would, under his watch, quickly recover to make the first £1bn annual profit in British industrial history?

In the circumstances, "on his watch" is an apt expression - for two reasons. Firstly, Harvey-Jones did not spring from business school, but from the bridges of boats. He joined ICI in his early 30s, after resigning his commission as a Royal Navy lieutenant commander in 1954. He spoke little of his exploits as a wartime submarine commander, and less of his cold war work in naval intelligence.

His naval career began in his teens, when he was enrolled at Dartford at the end of an unusual but unhappy childhood. Born an only child in Hackney, east London, he was quickly moved to India, where his father, a colonial administrator, became the guardian and tutor of a boy maharajah in the kingdom of Dhar.

A lifestyle of tame elephants and servants swiftly changed when, despite his enduring love for his mother, Harvey-Jones was shipped back to prep school in England, where "I spent my seventh birthday having the daylights whammed out of me".

Some accounts suggest he would spend the rest of his life trying, despite this early havoc, to impress and then emulate his father. This was clearly the view of the journalist Lynn Barber, who, in 1991, portrayed him as a whisky-swigging misogynist. Yet he lived very simply with his wife Betty and their only child, a daughter, Gaby, in Ross-on-Wye, Herefordshire. Fellow ICI executives and journalists were very seldom invited to their home.

His adult life seems to have been shaped when, in 1954, his daughter caught polio, just months before the Salk vaccine was discovered, and became severely disabled. Virtually overnight Harvey-Jones threw up his naval career and took a job as a time-and-motion study man at ICI. How he got from this ordinary job on Teesside to the top of the company has never been properly chronicled, despite the series of books he later wrote.

He was once described by a colleague as being like a knockabout circus performer who actually made work enjoyable. The media loved him because he was so outrageously upfront and honest. When asked what he thought of ICI's performance in his first year as chairman, he replied: "Lousy."

A year or two later, as he struggled to turn the company around, he was asked by a foreign journalist why he thought Britain's recession was deeper than other European countries. "That's simple," he said. "It's because we've got Margaret Thatcher running the country."

Harvey-Jones believed that the combination of Thatcher's free market zealotry and Fortress Britain mentality were killing the country's industrial core. In his 1986 Dimbleby lecture, he remarked: "If we imagine the UK can get by with a bunch of people in smocks showing tourists around medieval castles, we are quite frankly out of our tiny minds."

It was these sort of remarks that made him so popular on television. He became a regular on BBC's Question Time and even braved Professor Anthony Clare's In the Pyschiatrist's Chair on Radio 4, where he wept about Gaby's illness and called his father a "born loser, compulsive line-spinner and great boaster".

The BBC Troubleshooter series made Harvey-Jones a household name. Millions watched him telling organisations such as the Morgan Cars company how they should resurrect, or at least restructure, their businesses. He was a great performer, even if his commercial advice was not always sound. He told Morgan, for example, that they should cut their years' long waiting list - when it was the cachet of having to wait so long that made a Morgan so tantalisingly desirable. But the series was a great success. The public loved his gritty honesty. Producer Robert Thirkell said Harvey-Jones was a joy to work with. Thirkell never let him speak in advance to the businessmen he was about to interview, even though Harvey-Jones's natural instinct was to chat before the start of filming. But regardless of this, his detractors believe he was mostly show and of little substance, and that he was fortunate that his time at ICI coincided with the company's natural recovery.

For others, Harvey-Jones was an inspiration, a visionary who cut through the swathes of British bureaucracy and blue-stocking stuffiness with his bluff language and bolshy persona. For him, ICI and other British companies could survive only if they got streetwise and learned to invent products where there was money and a market.

But the price was very high. Under him, profits may have soared, and ICI recovered its fame to merge with the pharmaceuticals company Zeneca, but it was only after thousands of jobs - mostly in Britain - were slashed in the bulk chemicals divisions. Harvey-Jones failed to see that ICI should have pulled out of South Africa, in support of the imprisoned Nelson Mandela, during the apartheid era; he failed to grasp quickly enough that CFC gases were destroying the ozone layer; he failed to appoint female executives. He even allowed salt mines under ICI's Billingham complex in County Durham to be targeted, although not ultimately used, as a repository for nuclear waste.

Despite his public loathing of Thatcher, he accepted her offer of a knighthood in 1985. He was voted Industrialist of the Year in 1988 for the third consecutive year. He retired from ICI in 1987 and took up a series of relatively untaxing directorships, including the Economist, where he was chairman, and Grand Metropolitan. He suffered a stroke in 1994, but characteristically plunged into physio and speech therapy and was back in front of the Troubleshooter cameras six weeks later. Another stroke hit him in 1996. Betty and Gaby survive him.

· Sir John Henry Harvey-Jones, business executive, born April 16 1924; died January 9 2008